THEORETICAL FOUNDATIONS OF BIOMEDICAL ENGINEERING
IN NONINVASIVE MEDICAL SPECTROPHOTOMETRY
The developing and devising of general engineering theory of projecting and creation of new diagnostic apparatus and systems for noninvasive laser medical diagnostics and spectrophotometry (NMS) is an interesting and promising problem in a modern biomedical engineering. Being widely used and tested today in different countries, in different clinics and in different branches of medicine, these new medical equipment haven't got a fundamental engineering theory on projecting, constructions, simulations of them, etc. It is clear, that a common theory approach to creation of any medical, optics and/or electronic equipment is valid in this case as well. But it is also well known, that any new class of diagnostic systems, especially medical, has its own specialties, which cause some specialties on all stages of the system's creation. From first stages of ideological-technical designing of them up to stages of development of system's software, methodological and metrological ware, etc.
For this purpose in our study basing on the example of a multifunctional laser noninvasive diagnostic system (MLNDS) the scientific-engineering formalization of an object description of the problem was made. A tested biological object (BO) is supposed to be described as a nonlinear optical filter, coding the illuminating light (amplitude of its spectral components, pulses time delays, etc.) in accordance with the BO’s morphological and biochemical composition. So, the united aim-function of MLNDS can be formulated as the decoding of a registered from BO light in terms of morphological and biochemical properties of the BO. Basing on that the structure-functional model of generalized MLNDS was developed. It is shown that five main functions must be executed by MLNDS’ hardware – an illumination of BO by known power of different wavelength light, the registration of a coded light from BO, the separation of that in two different arrays (low-power static optical signals in supplementary spectra and fast changed signals of initial spectra), the conversion of optical signals to electrical ones and the digitalization of electrical signals. All other functions can be executed by up-to-date system’s software.
Moreover, it was shown, that exactly all possibilities of system’s software to calculate accurately any morphological and biochemical properties of BO dictate to designer a necessity of the using of concrete wavebands, spectral power, time rate, etc. that all in total defines a systems' hardware architecture and specialties. So, it is grounded a key role of system‘s software in all problems of architecture construction of MLNDS on the stage of the ideological-technical designing of that. Additionally, the basic principles of block-modules composition of hardware of MLNDS were formulated in the study as well. Almost all modules and hardware’s units of MLNDS can be constructed today as a standard blocks and units which are produced by different companies and firms all over the World. So the main function of a modern designer of MLNDS’ hardware consists in a synthesis of the system in a total with the use of standard, conventional and serial optoelectronic units and blocks.
And one more very important problem. Any diagnostic (measuring) technologies make sense only when it is possible to compare results of different measurements (by different devices, on different patients, on the same patient in different days etc.) among themselves and to do a conclusion about reliability of distinctions for different measurements or about an absence of the distinctions. For this purpose the measuring technologies should have the corresponding standardized metrological maintenance and questions of accuracy, reproducibility, reliability, repeatability and comparability of results of such measurements should be clear and studied. Today all these problems of metrology of measurements in NMS are studied rather poorly, and the standardized and certified measuring apparatuses for NMS completely are absent not only in our country, but also in the world as a whole. Disputable there is a question and accuracy and reliability of such measurements. And it opens additional wide prospects for scientific researches in the field of NMS.
For more information see our publications:
1. Rogatkin D.A. "The Laser Clinical Diagnostics as One of the Perspective Branch of Biomedical Radio-Electronics and Medical Physics of the Next Millenium" // Biomedical Radio-Electronics, No. 3, 1998. - p. 34-41. (in Russian)
Have a look at the paper (Russian version) in PDF (1300 KB)
2. Rogatkin D.A., Prisnyakova O.A., Moiseeva L.G., Cherkasov A.C. "Analysis of the accuracy of clinical laser fluorescence diagnosis" // Measurement Techniques, Vol. 41, No. 7, 1998. – pp. 670-674.
Have a look at the paper in PDF (341KB)
3. Rogatkin D.A., Lapaeva L.G., "Prospects for development of noninvasive spectrophotometric medical diagnosis", Biomedical Engineering, vol. 37, No. 4, 2003. – p. 217-222.
Have a look at the paper in PDF (116KB)
4. Rogatkin D.A. "Basic principles of organization of system software for multifunctional noninvasive spectrophotometric diagnostic devices and systems" // Biomedical Engineering, Vol. 38, No. 2, 2004. – p. 61-65.
Have a look at the paper in PDF (90 KB)
5. Dmitriev
M.A., Feducova M.V., Mustafaeva D.M., Kolbas Yu. Yu., Rogatkin D.A., Bychenkov
O.A., Polyakov P.Yu. "New portable noninvasive spectrophotometric apparatus
for clinical diagnostic application" // Proc. SPIE, vol. 5474, 2004. – pp.
331-338.
6. Amzina M.V., Micheev A.A., Rogatkin D.A., Sidorov V.V. "Combined medical diagnostic system with separated Laser-Doppler and reflectance oximeter channels" // SPIE Proc., vol. 6163, 616317 (2006).
Have a look at the paper in PDF (482KB)
7. Bessonov A.S., Kolbas Yu. Yu., Rogatkin D.A. "Virtual diagnostic apparatus in medical noninvasive spectrophotometry" // Technology of living systems, vol. 4, No. 1, 2007. - p. 50-57. (in Russian).
8. Rogatkin D.A., Lapaeva L.G. "Complex bio-technical approach on a stage of ideological-technical designing of multifunctional diagnostic systems for noninvasive medical spectrophotometry" // Biomed. Technology and Radio-Electronics, No.8-9, 2008. - p.89-97. (in Russian)
Have a look at the paper (Russian version) in PDF (336 KB)
9. Rogatkin D.A., Lapaeva L.G., Petritskaya E.N., Sidorov V.V., Shumskiy V.I. "Multifunctional laser noninvasive spectroscopic system for medical diagnostics and some metrological provisions for that" // Proc. SPIE, vol. 7368, 2009, 73681Y.
10. Rogatkin D.A., Dunaev A.V., Lapaeva L.G. "Metrological providing for methods and devices of non-invasive medical spectrophotometry // Biomedical Engineering, Vol. 44, No. 2, 2010. – p. 66-70.
Have a look at the paper in PDF (265 KB)
11. Rogatkin D.A., Makarov D.S., Dmitruk L.I. Informativeness and sources of errors of in vivo laser spectrophotometry methods in diagnostics of blood microcirculation disorders. // Abstract book of International symposium on laser medical applications – Moscow, A.M.Prokhorov General Physics Institute, 2010. – p.35-36.
Have a look at the paper in PDF (459Kb)
12. Rogatkin D.A., Sokolovski S. G., Fedorova K. A., Stewart N. A., Sidorov V. V., Rafailov E. U. Basic principles of design and functioning of multifunctional laser diagnostic system for non-invasive medical spectrophotometry // SPIE Proc., Vol. 7890, 2011. - 78901H
Have a look at the paper in PDF (251KB)
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